Gas-burner.



D. ANDERSON.

GAS BURNER.

APPLICATION rum) r1212. '1, 1914.

1,095,540, Patented May 1914- DAVID ANDERSON, OF LONDON, ENGLAND.

GAS-BURNER.

Specification of Letters Patent.

Patented May 5, 1914.

Application filed February '7, 1914. Serial No. 81?,240.

To all whom it may concern Be it known that I, DAVID ANDERSON, subject of the King of Great Britain and Ireland, residing at London, England, have invented certain new and useful Improvements in Gas-Burners; and I do hereby declare the following to be a full, clear, and exact clescription of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to gas burners, burning mixtures of gas and air, and has for its object to prevent back-firing on ignition and extinction of such burners.

I have found that back-firing can be prevented without any necessity for changing the direction of the passage of the mixed gas and air to the burner, and without the use of any device, such as wire gauze or small tubes, which interfere with the velocity of the mixture supplied at any given pressure.

The invention consists in flattening the portion of the tube leading to the burner so that the two walls of the tube approach closely toward each other for a short distance along the tube.

The invention further consists in the improved means for preventing back-firing in gas burners on ignition and extinction as hereinafter described.

In carrying the invention into effect according to one example as applied to a single inverted incandescent burner, I provide a 15.5 mm. tube leading from the gas supply to the burner, the size of the tube being suitable for standard inverted burner nozzles as at present in use. For a length of about 50 mm. of this tube close to the burner I form a flattened portion by merely hammering or pinching the sides of the tube toward each other until a flat passage of about 3 mm. depth is formed. I find that when this tube is used instead of the usual circular tube leading to the inverted burner all danger of back-firing on ignition and extinction of the burner is completely avoided.

I will now proceed to describe this invention more particularly with reference to the accompanying drawing in which Figure 1 is a sectional elevation showing one method of carrying this invention into eflect, Fig. 2 is a different sectional elevation of Fig. 1, Fig. 3 is a part sectional plan of Figs. 1 and 2, Fig. 4 shows the invention as applied to a group of burners, Fig. 5 is a part sectional plan of Fig. i.

In carrying this invention into effect as illustrated in Figs. 1, 2 and 3, in which is shown the invention applied to an inverted incandescent burner, the pipe 1 leading from the air inlet head 2 to the burner 3 is constructed so that at one part the walls a and 5 approach each other over a short distance along the pipe. The vertical distance of this flattening is directly dependent upon the area of the pipe unfiattened, for instance, if a pipe of 15.5 mm. be employed, a satisfactory result would be obtained by bringing the walls of the pipe together so as to provide a fiat space approximately 3 mm. across for a length of 50 mm. or approximately thereabout, The length of the flattened portion should not be less than this proportional minimum, but the invention is quite as efiective if the length be increased within reasonable measurements beyond this minimum. Both the incoming and the outgoing ends of the flattened portion should be suitably shaped so as to give a free flow of gas into and from the flattened portion.

It has been proposed to increase the flattened portion in a direction at right angles to its length, but as a result of experiments I have found that this increase in width of the flattened portion is not necessary, as the increased velocity given to the gas in being passed through the restriction in area occur-, ring in the flattened portion is sufiicient to prevent back-firing taking place.

In Fig. 4 I have shown a modification wherein the invention is applied to a group of burners which are suspended from the flattened gas tube 1, which is the equivalent of the arrangement shown in Fig. 1. In the form of construction in Fi 4c the pipes from the supply are provided with a breeches union 7 and connected to a circular or other shape flattened ring 1. The burners in this case are staggered so as to avoid proximity to the incoming gas pipes 6 as shown in Fig. 5, it being necessary to preserve the minimum distance between the burner itself and the source of supply with the intervening length of flattened tube. A deflector 8 is disposed above the flattened tube. This helps to raise the gas to a higher temperature, and considerably increases its illuminating properties.

It will be seen that this device may be provided in practically any gas installation without the need of extensive structural alterations and the invention is equally applicable to other burners than burners for incandescent lamps, the invention finding application in stoves or other devices in which burners using mixtures of gas and air are employed. 1 have also found that the invention is applicable in cases where both high and low pressures gas is employed.

I claim l. The combination, with a supply pipe for a mixture of gas and air, and a gas burner; of a flattened connecting pipe interposed between the said parts and having a passage the area of which does not exceed that of the supply pipe and which is relatively narrow in proportion to its Width and which operates to prevent back firing at the burner.

2. The combination, with a forked supply pipe for a mixture of gas and air, and a series of gas burners; of a flattened annular connecting pipe interposed between the said parts and having a gas passage the area of which. does not exceed that of the supply pipe and which is relatively narrow in proportion to its width and which operates to prevent back firing at the burners.

In testimony whereof I have affixed my 30 signature, in presence of two witnesses.

DAVID ANDERSON.

Witnesses:

H. D. J AMESON, L. E. BOWIE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, I). C. 

